This application works like an HTTP server and provides web interface for HostMonitor. It means you can install Web Service on a local or remote system and check (and control) HostMonitor in real time using a web browser on any computer that is connected to the Internet.

In addition to the standard web interface (available by http://web_server_address/index.htm link) Web Service provides a second one, which is more suitable for mobile devices with a small screen (PDA, smart phone).

Yes. I know I can use web interface from web service but it will raise some security issues. Most of the companies keep their monitoring systems behind firewall and to access HostMoitor web page we must publish it on DMZ which is not secure but when you have application you can control it.
Thank you,

Sorry, I do not see any difference from security point of view.
In any case you will need to open some port on your firewall in order to access Web Service, HostMonitor or any other application.

Web Service supports SSL so all traffic between your iPhone and Web Service can be encrypted.
Traffic between Web Service and HostMonitor is encrypted as well, so you may install Web Service outside of protected network.

If we implement any other application, why do you think it will be more secured (or why do you think Web Service is less secured)?